It is the general objective to study the macromolecular make-up of the structure bounding the Cochlea duct, the vestibular labyrinth and the respective fluids in mammals, and corresponding entities in the bird. The structures emphasized are tectorial membrane, basilar membrane, spiral ligament and spiral limbus, cupulae, statolithic membranes and the epithelia of the maculae, as well as otoconia, and the basilar pappila. The methods to be used are 2D-PAGE, mass spectrometry, immunochemistry and gene cloning. The biochemical features of the tissues and fluids to be studied, when integrated with their structural and biophysical properties will provide a better understanding of cochlear and vestibular biomechanics in health and disease. The studies on the avian ear will shed light on the role of the supporting structures in the regeneration of hair cells.